One conventional approach to monitoring heart function is transesophageal echocardiography (TEE), in which a probe containing an ultrasound transducer is inserted into the esophagus and positioned so that the transducer is near the patient's heart. The probe is then used to capture video images of the heart in real time, which are typically displayed on a video monitor. Conventional TEE probes typically measure between 10-15 mm in diameter (for adults). Because of this large diameter, conventional TEE often requires anesthesia, can significantly threaten the airway, and is not well suited for long-term monitoring of the heart. More recently, smaller TEE probes that permit long term monitoring and eliminate or reduce the need for anesthesia have been developed, as disclosed in US2005/0143657 (application Ser. No. 10/996,816, filed Nov. 24, 2004).
Under certain circumstances, operating a TEE probe at a high frame rate can cause the probe's temperature to increase by an undesirable amount. This can be particularly problematic with smaller probes, where less surface area is available for dissipation of the applied power.